Basically I would be in a interaction with a girl and as some puas suggest I'd imagine fucking her or her licking my dick while being direct or using shock and awe and after that I'd noticed I'd go to the toilet and I seem to cum a little bit. In other words jizzed in my pants.

What do you think is the reason for that. How can I prevent this from happening?

Precum. It's normal, look it up and don't worry about it. She'll never notice that as you pull your clothes off, she's more wet than you are.

Your main problem is the sex itself. You should feel horny, but you are not supposed to imagine this in your head man. You are getting the action in real life, then why picture this in your head? Just let the sex flow easily and concentrate on making her feel good and giving her orgasm. This way you won't pre cum. If you still do that, try some exercises like Kegel exercises. Perform this exercise anytime you are sitting down and in a relaxed state. Watch for the effects, they build up eventually. And, again, DO NOT think about having sex when you are HAVING sex, just have sex, make her feel good about herself, and she will help you to get your rocks off.

Just use the bathroom and wash it before. And yes, precum is there to lubricate your penis, it is normal.

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I'm not trying to be a dick Ezo, but you're being a Pick Up Snob in my opinion.

bbardot: you just reminded me about porn